Periscope with compass attachment.



G. H. BEDELL.

PERISCOPE WITH COMPASS ATTACHMENT.

APPLICATION FI LBD OOT.8, 1910.

Patented Nov. 5, 191 2.

2 SHEETSSHEET 1.

-' lNVENTOR BY /W' WITNESSES:

W ATTQRN EYS C. H. BEDELL.

PERISGOPE WITH COMPASS ATTACHMENT. APPLICATION FILED 00T.B. 1910.

1,043,562. Patented N0v.5,1912.

2 SHEETS-BHEET 2.

, INVENTOR ATTORNEYS UNITED STATES PATENT OFFTCE. CHARLES H. BEDELL, 0F 'WOEIlAS' ION, MASSACHUSETTS, ASSIGNOR TO ELECiTRIC BOAT COMPANY, OF NEW YQRK, N. Y., A CORPORATION NEW rnnrscorn WITH COMPASS ATTACHMENT.

Specification of Letters Patent.

Patented Nov. 5, 1912.

Application filed October S, 1910. Serial .No. 585,958.-

To all whom it may concern.

Be it known that 1, CHARLES H. BEDELL,

a citizen of the United States, residing at VVollaston, county of Norfolk, State of Massachusetts, have invented certain new and useful ImprtRements in Periscopes with Compass Attachments; and I do hereby declare the following to be a full, clear, and

exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in periscopes for submarine craft and the like, in which the image of the observed objects is produced in conjunction with an image of a compass scale in such relation thereto that the position ofany particular object in the,

field of view is determined more accurately and more speedily.

' In accord ance with my invention the compass is removed to a point within least magnetic influence of the boat and the image ofits scale is produced in conjunction with the image of the observed objects embraced in the field of view, so that the resultant image immediately discloses, by use of cross-hairs,

both the particular objectunder ob'servation and its definite'compassbearing, and with minimum error dueto magnetic disturbances.

In the accompanying drawings forming a part of this specification, and illustrating the preferred embodiment of my invention,

Figure lis a sectional elevation ofthefupper part of the periscope showing the compass, prisms and-.lenseslocated therein; Flg. 2 1s an illustration ofthe graduated scale of the compass. The optical system is such as to invert the image of this scale, and in. consequence the numbers should be arranged thereon as viewed in a mirror, but in the drawing'fii'ey are shown in the ordinary arrangement, to avoid confusion. .Fig. 3 shows the associated images of the observed objects in the field oflviewand a portion of the graduated scale; Fig. 4 is an elevation,

partly in section, of the periscope and its housing in a conning tower; Fig 5 is a diagram of the optical system comprising prisms and lenses. T

The periscope consists of a tube 1 to which is secured at 2 a top part 3 having light inlets 4 and 5 of clear glass. The light from the observed objects within the field of view enters at the light inlet 4 and, preferably, a

part of it is obstructed by the prism 6 while the remaining part passes into the prism 8. The glass window 5, or any source of light, illuminates the compass scale or card beneath it. A part of this light then passes through the prism 6 and the lens -7 in proX- imity thereto, and then in conjunction with the light from the field of view entering at 4, passes into the prism 8. The'combined light is reflected and transmitted by an ordinary optical system. comprising the prisms 8 and 12 and lenses 22,.9, 10, 11 and 13 to the eye ofthe observer placed at'the eyepiece 14. Thus, in the eyepiece 14 is seen the image of theobserved objects within the V field of view combined with the image of a part ofthe compass scale, as illustrated in Fig. 3. p p

The compass comprises a pivot-point of support 15 for the magnet 16 which carries a compass card or graduated circular scale- 17.. The compass card is in line with the pivot point, so that correct readings will be obtained,even when the tube 1 stands at an angle with the perpendicular. Preferably the center of the compass card is in a vertical plane with the center of t-h'einlet 4, and the prism 6 is so arranged that the image of that portion of the graduated scale of the compass which is immediately adjacent to this vertical plane is associated with, the

image of the distant objects in the field of view, as shown in Fig. 3.' Lens 7 is so placed and proportioned that the light: passing through it from the compass card is brought to a 'focus in the same plane as the light from distant objects in the field of view. Thus the images of the distant objects in the field of view and the image of the compass card are seen clearly withthe same 'setting'of the eyepiece.- In operation the vertical cross-hair 18 is laid upon any desired object-in the field of view by turning the periscopeby means of, the worm 19 and gear 20, and the c'ompassbearing of the ob- 'ject' is then determined by the intersection of the vertical cross-hair with the image of the graduated-scale. The cross hairs are preferably located in the eye piece except in the case of a rotatable periscope with'a stationary eyepiece, in which case the cross hairs are preferably in the rotatable memher. If desired thehorizontal cross hair may be omitted.

An incandescent lamp 21 may be used for additional illumination within the perisco e, in order to provide suificient light on du l or dark days, or such artificlal 1llum1na-" tion may be relied upon entirely, the glass 5 in that case being replaced by an opaque cover. When such an incandescent lamp is used, the prism 8 may be covered with a shield as indicated at 21 in Fig. 1.

- more, the system of light rays coming from the field of view and the system of light rays com-ing from the compasscard have, as viewed through the eye-piece, parallel axes so that they appear to lie in the same direction. In the preferred form of the'invention, the prism 6 is so arranged that it intercepts a part of the light rays from the field of View, thus shadowing or screening oil a part of that field, and the light rays from,

the compass-card are so introduced that they a lie within this shadowed or intercepted portion of the field of view, so that'to an observer at the eye-piece, the field of view and the compass-card are together visible in juxtaposition, as indicated on Fig. 3 of the drawings.

It is apparent that the construction herein described may be modifiedin many details without departin from the essential features of my invention. The system of prisms and lenses may be modified in any well known manner; and the light inlets or the substitutes therefor may bearranged in any other relation, the essential condition being that the relation be properly included in determining the angular position of the object in the field of view; v

It will be-observed that in the preferred embodiment of the invention described the compass is compactly mounted at the top of the periscope tube, without substantially enlarging the tube, and is removed to the greatest possible distance from the magnetically disturbing hull of the boat.

Having thus described my invention, what I claim is: y

1. In combination with a periscope, a compass having a scale, means ;for illuminating said scale, an inlet for lightfroin the field of view, and an optical system so arranged that the. image Ofsaid, scale is'combined with the image of the objects within the field oi view substantially as described.

an objective adapted to ipeaeca compass having a scale, a light inlet for illu minating said scale, an inlet for light from the field of View, and an optical system so arranged that the image of said scale is combined with the image of the'objects with in the field of view; substantially as described.

3. In combination witlfa perisco e, a

compass having a scale, means for i1 uminating said scale, aninlet for light from the field of view, and an optical system, the said apparatus being so arranged that the central line of the image of said scale coincides with the central line of the image of the field of View; substantially as described.

4. In combination with a periscope,a compass having a scale, said scale, an inlet for light from the field of view, an optical system, means for turning the periscope, and a hair-line, said apparatus being so arranged that the compass bearing of an object within the fiel of view is indicated by the intersection of the said hair-line with the image of the object and the image of said scale; substantially as described.

5. A periscopetubc containing an optical system for observing objects within the field of view, in combination with a compass having a graduated compass card in the upper end ofthe periscope tube, means for illuminating the compass card, and suitable light deflecting means adapted to produce an 1mage of a part only of the compass scale in conjunction with the image of said objects; substantially as described. I

6. A eriscope tube containing an optical system or observing objects within the field of view, in combination with a compass having a graduated compass card in the upper end of the periscope tube, means for illuminating the compass card, and suitablelight deflecting means associated with said optical system and adapted to produce an image of said objects in conjunction with an image of that portion of the compass scale which lies immediately adjacent to a vertical plane passing through the center of the observing orifice of the periscope tube; substantially as described. 7 A periscope tube having a compass with a graduated compass card at its upper end, means for illuminating the compass card, and a suitable optical system for producing at the lower end of thetube an image of the compass card; substantially as described.

8. A periscope having an eye -pi'ece and e directed to a field "of View, in combination with a magnetically directed compass-card and a second objecfields of said two objectivesjbein'g."together visible in said eye-piece; sub anb'tally as de- I scribed. 2.111 combination with a periscope, a

9. A periscope having an eye-piljce and an means for illuminatin 'tive focuse'dupon said compass dard, the

objective adapted to be directed to a field of jectives are together visible in juxtaposition new, in combination with a magnetically diin said eye-piece; substantially as described. 10

rected compass-card, a second objective fo- In testimony whereof I afiix my signature, cused upon said compass-card and a lightin presence of two witnesses.

deflecting element-screening a part of the 'CHARLES H. BEDELL. rays from the field of View and deflecting Witnesses: into the place thereof rays from the com- 'F. L. BRAKE,

pass-card, whereby the fields of said two ob- W. D. FESLER. 

